A known class of actuator is arranged so as to be biased to assume an intermediate condition which lies between a compressed condition and an extended condition in terms of the extension state of the actuator. Such actuators will be referred to herein as “centre seeking”. When operated, a centre seeking actuator will oppose an applied force which acts to move the actuator from the intermediate condition.
As such, a centre seeking actuator may be used to bias a first part of an assembly to move to a predetermined position relative to a second part of the assembly and oppose relative movement from the predetermined position.
The present inventors have identified that known centre seeking actuators can be improved in terms of enduring the various operational states of an assembly.